Circuit-breaker for glower-lamps.



Np. 652,702. v Patented June 26,1900.

' A. J. wums.

CIRCUIT BREAKER FOR GLOWER LAMPS.

(Application filed June 9, 1899.) (No Model.)

,, M 5 g I a... My.

"In: News PETERS co. vuoro-uwa. WASHINGTON, a. c,

ALEXANDER JAY l/VURTS, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO GEORGEWESTINGHOUSE, OF SAME PLACE.

CIRCUIT-BREAKER FOR GLOWER LAMPS.

SPECIFICATION forming part of Letters Patent No. 652,702, dated June 26,1900. Application filed Tune 9, 1899. Serial No. 719,886. (No modrl.)

To all whom it nz/(ty concern:

Be it known that I, ALEXANDER JAY WURTS, a citizen of the United Statesof America, and aresident of Pittsburg, in the countyof Allegheny andState of Pennsylvania, have invented certain new and useful Improvementsin Circuit-Breakers for Glower-Lamps, of which the following is aspecification.

In electric lamps wherein the incandescing elements are formed frommaterials which are non-conductors when cold, but become conductors whenbrought to a su fticiently-high temperature, the practice has been toemploy an electrical heating device the circuit of which is controlledby a solenoid or other electromagnetic appliance which is adapted tobreak the circuit of the heater automatically when the glowers havebecome sufficientlyheated to conduct current themselves.

,The arrangement has been such that the solenoid or otherelectromagnetic appliance has been operated by the current which passedthrough the incandescing elements after they have become sufficientlyheated. The failure for any reason of one or more of the glowers orincandescing elements to convey current after having once come intooperation would act to lessen and perhaps wholly interrupt the currentpassing through the solenoid, on which account there might be danger insuch a case of the solenoid releasing its core and reestablishing theheater-circuit. The result would be that the heater might be caused togenerate heat to no purpose and might burn out and become inoperativewithout serving any useful end. My present invention is designed to makeit impossible for the heater thus to burn out, and, in fact, it preventsthe heater circuit from becoming closed even though all or nearly allof, the glowers should be extinguished. I accomplish this result byproviding in the lamp a switch which when first operated in order toclose the circuit and bring the lamp into action carries a stop ordetent into such a position that when the solenoid-core is once raisedto open the heatercircuit it will stand in the way of a hook or catchconnected with the said core and will prevent the latter from descendingand again closing the heater-circuit until the lamp is switched off. Insystems where lamps of the type described are used the invention which Iherein disclose lessens the need of frequent inspection, While if it isassumed that inspection is necessarily infrequent or likely to be so thepresent invention is even more important.

I have illustrated my invention in the accompanying drawings, in which-Figure 1 is a side elevation of a solenoid controlling a lamp system,and Fig. 2 is a plan of the same.

In the drawings, A is a generator of electricity, and B and O are themains leading therefrom. From these mains proceed wires 1 and 2, whichconstitute the circuit in which the glower 3 is included. The circuitdescribed includes the coils of a solenoid 4, which is provided with avertically-movable core 5. From the mains are also led ofi wires 6 and7, which are joined to the stationary terminals 8 and 9 of a switch, themovable terminal 10 of which is connected to the core 5 of the solenoid4:. The circuit 6 7 includes the primary 11 of a converter, thesecondary 12 of which is in'circuit with a heater 13, placed near theglower 3.

The circuit 1 2 is interrupted at the switchterminals 14 and 15, asshown, these terminals being bridged when desired by the switch 16,controlled byahandle. The glowercircuit is not completed until theswitch 16 is turned so as to bridge the contact-terminals 14 and 15. Theheater-circuit is, however, closed and ready for operation whenever thecontact-terminal 101s in contact with the terminals 8 and 9. When it isdesired to light the lamp, the switch 16 is operated by means of thehandle, so as to close the circuit 1 2. The heater-circuit being inoperative condition, the heater 13 will soon raise the temperature ofthe glower 3 until the said glower becomes itself a conductor. Thereuponthe circuit 1 2 will be made operative, the solenoid 4 will beenergized, and its core 5 will be lifted, thereby breaking theheatercircuit. Should the glower 3 burn out or for any reason cease toconduct the current, the core might under ordinary conditions return toits original condition and put the heater into action. This is sometimesunclesirable because of the danger of the heater itself becoming burnedout from excessive use. For that reason I have provided a hook or catch18 on the core 5 of the solenoid land have so arranged this catch withrelation to the switch 16 that when the latter is moved into positionfor closing the glower-circuit, as already described, its end will standbeneath the said hook or catch and prevent the descent of the core 5beyond a certain limit. Accordingly the terminal 10 cannot go back intocontact with the terminals 8 and 9, and thus the danger of burning outthe heater-. circuit is avoided. On the other hand, as soon as theglower 3 is thrown out of circuit by the operation of the switch 16 theend of the said switch is removed from beneath the catch 18, and thecore 5 is free to descend into its original position.

It is not necessary that the retaining device should be in the form of acatch or detent such as is shown. Instead of that the core of thesolenoid might in its movement for breaking the heater-circuit bebrought into contact with a permanent magnet, which would hold it in itsretracted position until it was positively restored to its originalplace.

I claim as my invention a 1. In a lamp wherein a glower of materialwhich is a non-conductor when cold and aconglower, anautomaticcircuit-breaker for the said heater-circuit, a circuit for thesaid glower, the said glower-circuit including a suitable switch, thesaid switch when closed serving as a catch or detent for preventing therestoration of the automatic circuit-breaker and being adapted to tripthe said circuitbreaker when opened.

Signed by me at Pittsburg, Pennsylvania, United States of America, this6th day of June, 1899.

ALEXANDER JAY WURTS.

Witnesses:

WESLEY G. CARR, H.- C. TENER.

